Subtract 90/42 from 45/40
1st number: 1 5/40, 2nd number: 2 6/42
45/40 - 90/42 is -57/56.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 42 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 40 × 21 = 840,
45/40 = 45 × 21/40 × 21 = 945/840 - Likewise, for the 2nd fraction, since 42 × 20 = 840,
90/42 = 90 × 20/42 × 20 = 1800/840 - Subtract the two like fractions:
945/840 - 1800/840 = 945 - 1800/840 = -855/840 - After reducing the fraction, the answer is -57/56
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